Reduced friction lift pin

Abstract

A substrate support is provided that features a lift pin having at least one larger diameter shoulder section that forms a relief region between the lift pin and a guide hole disposed through a substrate support. The shoulder section minimizes contact between the substrate support and lift pin guide hole, thereby reducing pin scratching, particle generation, component wear, and increasing the useful life of the pin. In another embodiment, a flat-bottom tip is provided to promote self-standing of the lift pin, reducing pin tilting or leaning of the lift pin within the guide hole.

1 . An apparatus for selectively spacing a substrate from a substrate support, comprising: 
 a substrate support having a lift pin guide hole disposed through the substrate support;    a lift pin shaft disposed within the lift pin guide hole, the lift pin shaft having at least a first shoulder section circumscribing a portion of the lift pin shaft and disposed movably within the lift pin guide hole; and    a lift plate disposed proximate an end of the lift pin.    
   
   
       2 . The apparatus of  claim 1  further comprising: 
 a lift pin guide disposed through a portion of the substrate support and having the lift pin guide hole formed therein.    
   
   
       3 . The apparatus of  claim 1 , wherein at a gap is defined between the lift pin guide hole and the lift pin, the gap bounded on at least one side by the first shoulder section.  
   
   
       4 . The apparatus of  claim 1  further comprising: 
 a second shoulder section disposed on the pin shaft in a spaced-apart relation to the first should section.    
   
   
       5 . The apparatus of  claim 4 , wherein the first shoulder section and the second shoulder section each comprise a rounded surface providing a bearing surface against the lift pin guide hole.  
   
   
       6 . The apparatus of  claim 1 , wherein the pin shaft further comprises: 
 a flat end; and    a flared head disposed opposite the flat end.    
   
   
       7 . The apparatus of  claim 1 , wherein the first shoulder section is comprised of a material different than the pin shaft.  
   
   
       8 . The apparatus of  claim 1 , wherein the first shoulder section is stainless steel and the pin shaft is ceramic.  
   
   
       9 . The apparatus of  claim 1 , wherein the first shoulder section is at least one of hard chromium plated or electropolished.  
   
   
       10 . The apparatus of  claim 1 , wherein the pin shaft comprises one or more sections of lesser diameter than the first shoulder section.  
   
   
       11 . The apparatus of  claim 1 , wherein the first shoulder section includes tapered ends that transition the first shoulder section and the pin shaft.  
   
   
       12 . An apparatus for selectively spacing a substrate from a substrate support, comprising: 
 a pin shaft having a first diameter section and a second diameter section;    a flared end adapted to support the substrate thereon and coupled to the first diameter section of the pin shaft;    a first shoulder section connected concentrically to the pin shaft between the first diameter section and the second diameter section, the first shoulder section having a diameter greater than the first diameter section and the second diameter section of the pin shaft; and    a substrate support having a hole formed therethrough, the hole having the first shoulder section of the pin shaft movably disposed therein.    
   
   
       13 . The apparatus of  claim 12 , wherein an end of the first shoulder section disposed away from the flared end is at a distance from the flared end that is less than a length of the hole through the substrate support in which the pin shaft is disposed.  
   
   
       14 . The apparatus of  claim 12 , wherein the pin shaft further comprises a flat end opposite the flared head.  
   
   
       15 . The apparatus of  claim 12 , wherein the first shoulder section is comprised of a material different than the pin shaft.  
   
   
       16 . The apparatus of  claim 15 , wherein the shoulder section is stainless steel and the pin shaft is ceramic.  
   
   
       17 . The apparatus of  claim 12  further comprising: 
 a second shoulder section disposed on the pin shaft in a spaced-apart relation to the first should section.    
   
   
       18 . A method for spacing a substrate from a substrate support, comprising: 
 elevating a lift plate to urge a plurality of lift pins in an upwards direction; and    moving the lift pins through a substrate support while maintaining at least a first contact point of each of the lift pins in contact with the substrate support while the lift pins move.    
   
   
       19 . The method of  claim 18 , wherein the step of moving further comprises: 
 maintaining a second contact point of each of the lift pins in contact with the substrate support while the lift pins move.    
   
   
       20 . The method of  claim 18 , wherein the step of elevating the lift plate to further comprises: 
 contacting the lift plate to a flat end of each of the lift pins to orientate each lift pin perpendicular to a plane of the lift plate.